


I've got a few things to say about these two

by Pomander



Category: Undertale (Video Game)
Genre: Deep Throating, Ecto-Genitalia (Undertale), Food Play, Kinks, M/M, Sanster, mostly in response to asks on tumblr, not dadster, very short drabbles
Language: English
Status: In-Progress
Published: 2017-07-05
Updated: 2017-07-05
Packaged: 2018-11-28 06:35:54
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 5
Words: 2,537
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/11412291
Author URL: https://archiveofourown.org/users/Pomander/pseuds/Pomander





	1. A strange display

“Hey, Doc, could you blow my nose for me?”

“Get that away from my face!” Gaster shouts, giving Sans a slight shove at the hip. The long, blue trunk wiggles sadly. It looks so much like that of an elephant. Gaster is wheezing, trying not to laugh any more. His ribs are starting to hurt. “My goodness. What made you think that was in any way arousing?”

“Aw, you don’t like it?” The trunk curls upwards, into a question mark shape. “I thought this’d do it for you, for sure.”

Gaster eyes the blue abomination, a mixture of curiosity and disgust welling up in him. “Can you…” he hesitates. “Can you make the n-noise with that? The trumpeting… you know.”

Sans plants his hands on his hips, looking down curiously at his own crotch. The tip of the trunk turns upwards to meet his eyes. “Not sure,” he admits. He turns to Gaster with a sly smile. “Wanna find out?”

“Not at all. Next!”

“Heh, alright.” The trunk dissipates and Sans’s magic coalesces in front of his pubis into a new shape, short and thick, with many flat-

“That’s a pinecone,” Gaster says flatly, pointing right at it.

“Sure is.” Sans crosses his arms triumphantly. “It’s a classic. An old favorite.”

“I’m not putting that in my mouth.”

“I wasn’t expecting you to, Doc.”

“Or anywhere else.”

“You won’t even just touch it? Just to try?”

Gaster sighs, closes his eyes, and reaches out with one hand, wrapping it gently- carefully around the pinecone. He’s expecting spikes along the underside of the scales, but there aren’t any. Just little nubs. He opens his eyes and looks at the thing, daring to grip it a little tighter. The scales fold gently toward the tip under his touch.

More importantly, it sends a cute little shiver through Sans as he squeezes. He feels a bit less reluctant now, he supposes, to put the thing in his mouth. He’d love to see the young skeleton’s reaction to such a move. He’s about to open his mouth and try it, but Sans speaks first.

“I’ve got one more idea,” he says, lowly. _Oh, this should be a treat._  

Gaster releases him and watches the form dissipate again, reshaping itself into a large, frilly orb of a flower, with many petals. _A peony. How lovely._  

“There’s a joke here, somewhere,” Gaster says, looking over the lovely little thing.

“Is there?” Sans asks, “I can’t think of one.”

“I know there is.” He reaches up to caress the petals lightly, noting the change in Sans’s breathing at his touch. He cirlcles the center of the flower slowly, moving inward. “It’s lovely, though.”

“Thanks,” Sans whispers, his voice trembling. 

Gaster smiles and brushes past the soft petals, pushing his thumb into the center of the flower, surprised to find it a bit deeper than he was expecting. The pistils in the center part for him, and his thumb sinks past them, into a moist space he’s sure isn’t part of any actual flower. He watches Sans’s knees shake.

“Does that feel alright, Sans?” he asks gently.

“Y-yeah,” Sans murmurs back.

The doctor smiles and turns to face him proper, pushing his mouth up against the flower. He breathes softly over the petals, watching them flutter. The magical construct doesn’t smell like a real flower, he notes, but it does smell like Sans, and that’s so much better. Sans quivers, placing his hands on Gaster’s shoulders to steady himself.  The doctor spreads the petals apart with his fingers, before leaning in closer and pressing his lips to the pistils, pushing between them, letting the stamen brush over the outside of his mouth.

The petals tickle his face, sending a thrill to his groin, and he pushes in further, to Sans’s wet core, drawing a long, quiet moan from him. His breath hitches, and he stumbles over Gaster’s name, tries again, and fails. Gaster circles his tongue between the pistils, sucking gently and pushing back in, repeating in a slow rhythm. 

Sans’s grip on his shoulder tightens, he’s close. Gaster sticks his tongue in as deep as it’ll go and swirls it around. “HHh, Gaster, fuck!” he hears the skeleton whine. He pulls his mouth away slowly, letting his lips linger, brushing across the anther and the petals gently as Sans’s shuddering ebbs away.

“I think I like this one,” Gaster purrs, licking the taste of his lover from his lips.


	2. Say it out loud

“Gaste-” 

“Say it. I want to hear you say my name. Loud and clear. Scream it if you have to.”

“Ghhhaaaah _oh god_.” Sans’s voice trembled, muffled by the blankets around his face as Gaster relentlessly fucked him into the bed.

Of course the doctor didn’t _actually_ expect him to enunciate at a time like this. In fact, Gaster kind of liked the whining cries of pleasure his lover made. He pumped his hips furiously, pushing as deep into Sans’s wet mound as he could.

“G-Gaster, Gaster, please,” Sans whispered. 

“I’m afraid I can’t hear you, Sans.”

“Hnnn -ve you.”

“Yes?”

“I love you.”

Gaster stilled, not quite to a stop, and Sans’s head turned toward him, staring up at him from the absolute mess of blankets under them. “I love you too,” he whispered.” His heart raced as Sans’s eyes met his own, then flicked away.

“Don’t stop?”

He felt his prick twitch. “As you wish.”


	3. Don't let me interrupt!

The postmonster’s long, leafy claws tremble, inches away from the heavy door. In their bag, at their side, is an important delivery, a package straight from Asgore Dreemurr himself. It needs to be signed for, and it  _has to be delivered today._

They know it’s probably a decorative coffee mug, but their orders still stand. And they still stand, in front of the recipient’s door, listening, though they know they should not be. The ability to knock has left them.

From the other side of the door, they hear the heavy, heady sounds of lovemaking, or whatever one might call it. Deep, breathy grunts join trembling whispers, and the deliverymonster swears they can hear pounding against the floor.

“You okay there, Doc?” a deep voice asks, barely audible.

“Y-yes. Yesss” the other voice replies, high and strained.

“You’re sure getting into this. I thought you weren’t into this kind of thing.”

“Hhhhplease. Don’t stop.”

“Yeah? Keep going? How much longer are you gonna last if I do, hm?”

Another rally of thuds sounds out against the floor. The deliverymonster hears a low chuckle and a loud gasp.

The front door of the next house over opens, and a tall monster in a business suit exits. The deliverymonster turns to them, eyes wide, red faced, and the two share a moment of confusion. 

“What are you doing?” The monster next door asks. 

“I-I’ve got a delivery for Mr. Magleon, b-but.”

“Oh, that’s me!”

“What?”

“You’re at Dr. Gaster’s house. I’m Mr. Magleon.”

The deliverymonster looks down at the package, and back up. He’s right, they were one door over from the correct address. Heaving a sigh of relief, they turn from the door and head down the step, eager to deliver the package to its rightful owner.


	4. Cream-filled

“Oh god… This is terrible. Once was bad enough.”

“You said you wanted to try it again, Doc. If you change your mind, let me know. If not, I’m more than happy to help you out.”

“Uuughghghgh.”

“Lay back, close your eyes.” 

Gaster does as he’s told. He lays there, trembling, anticipating something that in hindsight he really should not have told Sans he enjoyed. He knows he’s never going to live this down. But he really does want to try it. Sans takes hold of his member, strokes him until he’s good and hard, and without any further warning, his head is greeted with the cool, soft  wetness of whipped cream.

“Ohhhh,” he groans, “Oh this is strange.”

“Good strange or bad strange? Want me to stop?”

“Keep going. We’re in this too far now.”

Sans slips the cream horn further down Gaster’s dick, enveloping his shaft inch by inch. He opens his eyes and looks up in time to see a bit of the whipped cream pushing out the top of the pastry.

Sans leans down and licks the excess off the top. “No sense wasting it,” he says with a wink. Then he begins to stroke it up and down the length of Gaster’s prick. It’s just roomy enough that the pastry itself isn’t straining to hold together, and the texture… fuck the texture is fantastic. It’s soft and slick, and Gaster’s legs are tensing up and he’s shaking. He has no idea what to do with himself. 

“You doin’ okay?”

He doesn’t know how to answer. He tilts his head back into the pillow behind him, looks away. It feels amazing.

“I’ve got an idea,” Sans says. He lets go of the cream horn, leaving it at the base of Gaster’s dick, then stands up, pulls off his pants, and stands straddled over the doctor. “Hold it still for me?” he asks. Gaster does, and Sans sits down, carefully positioning the bottom of his pelvis over Gaster, pastry and all. It slides into him with no problem, and he quickly forms a small blue hand inside his pelvis to hold it in place. He grabs Gaster’s hands and brings them up to his hips. “How’s this?”

“Absolutely _obscene_.”

“Do you love it?” He slides his hips up slowly, then down, then up again.

“Yes.” Gaster whispers. His grip on Sans’s hips tightens. 

“Good, I want you to enjoy this.” Fuck, he says it so sincerely. 

The doctor looks down at where their pelvises meet, how the cream is being displaced by his prick and pushed out both ends of the horn. Sans loosens his grip a little, bounces his hips up a little faster. Gaster grabs tight to hold him still. 

“Let me,” he whispers. Sans nods and Gaster pushes his own hips up into the cream horn, into his lover. He bucks up again, harder, again, a bit faster. The damn thing likely won’t hold together forever, but he’s close to coming, and doesn’t care. He watches one of the sides split open at the edge when he thrusts, and it bumps up against Sans’s ischium, leaving a little smear of cream on the bone. He keeps going. Sans keens, and he plants his hands on Gaster’s chest for balance as Gaster does his best to absolutely wreck both him and the cream horn before he comes. 

He feels his thighs tense up, and an intense wave of pleasure rolls across his body, taking him over. He pulls Sans downward, into him as his cum spills up over the top of the pastry, all over the young skeleton’s pelvic bones and spine. By the time his orgasm is over, he’s still trembling. Sans climbs off of him, leaving the pastry on him as his dick starts to soften.

They lay down next to each other on the bed, each of them an absolute mess, not to mention the state Gaster’s sheets are likely in. Gaster reaches down and slides the ruined pasty off of himself, tossing it onto the table by his bed. He’s not going to even entertain the thought of eating it now. He looks down to Sans.

The inside of Sans’s pelvis is a mess of white smears and splatters. Gaster knows there are a few good ways to clean that up, one in particular that would have Sans squirming and calling out his name. That would be a good way to thank him for this, Gaster thinks. 

All in all, this was a messy experiment, and though he enjoyed it, he’s not keen to try it again any time soon. He looks over to his dresser, where the other eleven pastries still sit.

His resolve on that wavers.


	5. Thrussy

Gaster lies flat on his back, full nude, head hanging just over the edge of the bed. “I’m ready,” he says, licking his lips.

“Yeah?” Sans asks, waiting for another nod. “Here we go, then.” He slides his cock in between Gaster’s moistened lips, gripping the doctor by the shoulders for support. Gaster hums happily and runs his tongue in a circle around the head as it slips slowly into his mouth. “Woah, okay.” Sans takes a deep breath, “still good?” The relaxed vibrations of Gaster’s voice around him feel amazing, and he hopes that’s a yes. 

He moves his hips slowly, dipping himself into Gaster’s mouth at a careful pace, as the doctor sucks and swallows his dick. Looking over Gaster’s body, Sans watches the rise and fall of his chest, taking in deep breaths. Further down, he watches Gaster’s dick throb, already dripping with precum. “You like this?” he asks.

In response, the doctor wraps one hand around his own cock and begins to stroke it slowly. It’s hot as hell, and Sans maintains a careful pace, his eyes fixed to Gaster’s lap, until he feels a tapping at his own. He looks down to see Gaster’s hand on his thigh, and pulls out immediately. 

“Everything ok?” he asks, “Did I do something wrong?”

“I want more,” Gaster pants, “shove it in all the way, and don’t stop until you cum.” 

That makes Sans’s knees go weak. “I- you gonna be able to breathe, like that?”

“Don’t worry about it. I’ll let you know if it’s too much.”

“Uh, okay. Get ready.” 

This time, he shoves himself in slowly, all the way to the hilt. Gaster’s throat is wet and tight around his dick, and when he looks down, he can see a bulge in the front of it. He and the doctor moan in unison. 

“Fuck,” he whispers, “Okay, I’m gonna move.” He feels Gaster swallow, and swears he sees the doctor’s cock dribble a little. He pulls back a little, grabs Gaster under the arms for support, and thrusts back in again, deep as he can go. The tip of Gaster’s tongue peaks out past his lips, and sans shudders, slipping back out halfway and pushing in again. He begins to pick up a rhythm, mesmerized by the bulge moving up and down Gaster’s throat, the low moans that punctuate each thrust.

Gaster’s tongue pokes out just past his bottom lip. Sans pushes in harder, further, his feet struggling for purchase against the floor as he shifts his weight. “Shit, I’m gonna cum,” he whispers. Gaser moans loudly, rubbing up and down Sans’s leg, giving him the go-ahead. He keeps moving, tiny thrusts, just barely pulling out of Gaster’s throat as he spills himself inside. He doubles over, whispering the doctor’s name as he loses himself.

He opens his eyes after it’s over, marveling at the large pool of cum splashed across Gaster’s chest and belly. He feels another tap against his thigh, and slowly slides himself out of Gaster’s mouth. The doctor gives one final suck on the head of his cock, releasing him with a loud pop. It sends another jolt of pleasure through him, too much, and he curses, his knees finally giving way. He rests his head on the doctor’s shoulder while they both catch their breath.


End file.
